How to Submit Soil Samples

Printable Instructions: FlashPaper Document -- PDF Document

 Materials You Will Need:

  • Sample Soil Information Form (Click on the “Forms” icon to obtain this form – print 1 per sample)
  • Quart Size Zip-lock freezer bags
  • Collection tools (See graphic in Step 4 below)

General Instructions:

If the laboratory portion of your soil test is to be a reliable guide for completion of your recommendations, the sample you send must represent the soil conditions of the area sampled. 

Please read and follow all our instructions carefully.  The laboratory results will tell us only what is in the sample you send.  It is your responsibility to take a representative and unbiased sample of the area being tested.

When to Sample:

Soil samples can be taken any time of the year.  However, soil sampling is typically done prior to cultivation in the spring, and in early fall after the summer harvest is completed.

Special Information for International Customers:

Step 13 provides special shipping and handling instructions for samples being shipped from countries outside the United States.

Caution - Areas to Avoid When Collecting Samples:

It is important to avoid areas or conditions that are different, e.g., spots where fertilizer or lime have been spilled or recently applied, fertilizer band areas of last year’s crops, compost piles, field borders, and poorly drained areas.

Step-by-Step Collection Process

Step 1

Sketch Testing

On the reverse side of the Soil Sample Information Form, draw a sketch/map of the garden or mini farm field(s) you would like tested.

Be sure to show the major points of all adjacent areas, such as roads, other fields, buildings, shade trees, creeks or rivers, ponds, etc. surrounding the area you are testing.

(Mini farmers should draw a sketch of their entire farm.) The more detailed information you give the better.

Step 1

Sketch Testing

Sample Sketch/Map of a Garden*

* Reprinted with permission from A&L Eastern Agricultural Laboratories, Inc., Richmond, Virginia

Sample Sketch/Map 
of a Mini Farm Field*

* Reprinted with permission from A&L Eastern Agricultural Laboratories, Inc., Richmond, Virginia


Sample Differing Soils Separately

Soils that differ in soil type, appearance, or past treatment should be sampled separately.

If one area of your garden or mini farm appears healthy while another portion is growing poorly, sample each area separately. 

Avoid taking samples when the soil is too wet to till.

Step 2

Identify Each Sample Area on Map

On the map/sketch, assign a number for each field or garden plot being tested and assign a letter for each sample submitted from that field or garden plot.  Write these numbers and letters on your sketch/map.


Field or Garden Plot 1 – Sample A, Sample B, Sample C
Orchard, Vegetable Garden, Lawn

Step 3

Fill Out Soil Sample Information Form(s)

Fill out a separate Soil Sample Information Form for each sample you are submitting.  Be sure to complete this form in as much detail as possible.  The more information you provide on this form, the more accurate our recommendations to you will be.

Step 4

Start Collection Process

Start to collect the soil samples.

A soil-sampling probe, an auger, or a spade may be used to take soil samples. 

The most accurate samples are obtained with a soil-sampling probe. Gardeners do not need to go the extra expense of purchasing one.

Sample Collection Tools *

* Reprinted with permission from A&L Eastern Agricultural Laboratories, Inc., Richmond, Virginia

Do not touch the soil with your hands or use any galvanized, soft steel, or brass tools when taking these samples.  The best equipment to use for this type of sampling is a stainless steel or chrome-plated soil probe or spade.  Be careful to avoid any fertilizer dust contamination. 

Make sure you carefully follow the next steps as you take samples.  This is very important since the quality of the samples you take will have a direct bearing on the accuracy of your results and recommendations.

Step 5

Prepare Soil Surface & Bore or Dig

Scrape away the surface litter.  If a soil-sampling probe is used, obtain a small portion of soil by making a boring 8 inches deep for cultivated ground, gardens, pasture, and hay land and 6 inches deep for sod and lawns.  If a spade is used, dig a V-shaped hole to the sample depth - 6 or 8 inches - then cut a thin slice of soil from one side of the hole.

Step 6

Mark Sketch as Each Sample is Taken

As you go along, always mark an (X) on your sketch/map indicating where the samples were taken.  Use the sketch you drew to distinguish subareas in recording the location of samples.

Sample Scenario:  You find two soil types in the area you sample in Field or Garden Plot #1.  Simply mark one sample “A” and the other “B” from Field or Garden Plot #1.  (Example:  Field #1, Samples A & B)  Mark an (X) on your sketch/map indicating where samples A & B were taken.

Step 7

Label Bags

Clearly label each bag with your name and address, and the corresponding sample and field numbers you entered on the Soil Sample Information Form.  Keep a record for yourself of the area represented by each sample.

Step 8

Take & Bag Composite Samples

Because of soil variations, it is very important that each composite sample you submit consists of soil samples (cores) taken from approximately 15 to 20 locations in the sampled area for mini farms and 7 to 10 soil samples for gardens, raised beds, and small areas.  Walk a random pattern over the sampling area.  (See sketch map above)

After obtaining the required number of samples of soil, mix them together very thoroughly in a clean plastic bucket for your composite sample.  Do not dry the samples.  Place enough soil from the plastic bucket composite sample in a zip-lock freezer bag to fill the bag - approximately 1 1/4 pound of soil per sample.  Seal the bags tightly.

Step 9

Complete Soil Sample Information Form

Finish filling out the Soil Sample Information Form using as much detail as possible since this information is very important in making your soil test recommendations.  Be sure the sample number on this form corresponds with the number on the plastic zip-lock bag.

Note Regarding Follow-up Soil Samples:

When you are submitting follow-up soil samples previously tested by us, use the original sample number and note the original soil sample report number on the bottom of the Soil Sample Information Form.

Step 10

Pack Soil Samples for Shipping

Place all soil samples in a sturdy container and pack them tightly to prevent spillage during shipping. 

Note:  International customers please see Step 13 for special instructions.

Step 11

Seal Shipping Box

Before sealing the container, enclose one completed Soil Sample Information Form for each sample submitted and a check payable to Timberleaf Soil Testing for the number of samples enclosed.

Note:  International customers please see Step 13 for special instructions.

Step 12

Mail Box to Us

Send all soil samples & communications to:

Timberleaf Soil Testing
39648 Old Spring Road  
Murrieta,  CA  92563

Phone/Fax  (951) 677-7510


International customers please use the special address provided in Step 13.

Step 13

Procedure for Mailing International Soil


 Samples submitted from outside the United States are handled differently.

  • Your paperwork is sent to our home office in California.  (This includes the Soil Sample Information Form, your payment, and other correspondence/questions.)
  • Your soil samples are sent directly to our field lab in Richmond, Virginia.  Boxes containing soil samples require the special soil permit labels from the U.S. Customs Department described below.

To pack and mail samples from outside the United States:

Click on the “Forms” icon to obtain a U.S. Customs Import Soil Permit mailing form.  

Print one form for each box being mailed.  

Pack your soil samples in sealed, leakproof containers.

Before sealing the containers, add a note to each box saying:

         “Hold sample for instructions from Timberleaf Soil Testing”

Securely tape one U.S. Customs Soil Permit form on the front of each container.

Ship soil samples to

A & L Eastern Agricultural Labs Inc.
(Paul Chu)
7621 Whitepine Road
Richmond, Virginia 23237

Place all paperwork, e.g. the Soil Sample Information Form, your payment, correspondence, questions, etc. in a separate envelope.

Mail the paperwork to:

Timberleaf Soil Testing
39648 Old Spring Road
Murrieta,  CA  92563

Phone,  951-677-7510
E-mail address

39648 Old Spring Rd.
Murrieta, CA 92563

Specializing in soil testing for the Organic Grower since 1986


Happy Moose Web Design -